1. Technical Field
The present disclosure relates to a light-emitting device and a method for manufacturing a light-emitting device.
2. Discussion of the Background
Light-emitting devices that use semiconductor light-emitting elements such as light-emitting diodes are widely used, because the devices easily achieve reductions in size, and achieve high luminous efficiency.
The light-emitting devices that use semiconductor light-emitting elements are classified roughly into two types of: face-up type in which there are surfaces of the semiconductor light-emitting elements provided with pad electrodes on the side opposite to a mounting substrate; and face-down type in which there are electrodes provided on the lower surfaces of the semiconductor light-emitting elements as surfaces opposed to a mounting substrate.
In the case of the face-up type, semiconductor light-emitting elements are mounted on leads or the like, and the semiconductor light-emitting elements and the leads are connected to each other with bonding wires or the like. For this reason, in the case of a planar view from a direction perpendicular to the surface of the mounting substrate mounted with the elements, there is a need to locate the bonding wires partially outside the semiconductor light-emitting elements, and there is a limit on the reduction in size.
On the other hand, in the face-down type (flip-chip type), in the case of a planar view of pad electrodes provided on the surfaces of the semiconductor light-emitting elements and wiring provided on the mounting substrate from a direction perpendicular to the surface of the mounting substrate, electrical connections are possible with connecting parts such as bumps or metal pillars located within the range of the semiconductor light-emitting element size.
Thus, a CSP (Chip Size Package or Chip Scale Package) can be achieved which has a light-emitting device reduced in size (particularly, size in planar view from a direction perpendicular to a mounting substrate) to a level closer to a chip size of light-emitting elements.
Then, recently, in order to advance further reductions in size, or in order to further increase the luminous efficiency, face-down light-emitting devices are used which have growth substrates (light-transmissive substrates) such as sapphire removed or reduced in thickness.
The growth substrates refer to substrates used to grow thereon n-type semiconductor layers and p-type semiconductor layers constituting light-emitting elements, and also have the effect of supporting the semiconductor light-emitting elements which are small in thickness and low in strength, thereby improving the strength of the light-emitting device.
For this reason, a light-emitting device with a growth substrate removed or a light-emitting device with a grown substrate reduced in thickness after the formation of semiconductor light-emitting elements is configured to have a resin layer provided on the electrode side (on the side opposite to a mounting substrate) in order to support the semiconductor light-emitting elements, and have electrodes and external terminals electrically connected by forming internal wiring composed of metal pillars or other wiring so as to penetrate the resin layer, as described in, for example, Japanese Unexamined Patent Application Publication No. 2011-187679.
The light-emitting device can ensure sufficient strength, with the resin layer including the internal wiring.